When a television program is shown on a TV set, it is desirable that the TV set can recognize the current channel broadcasting the television program and notify the channel name to the user. Generally, digital TV sets can identify the currently broadcasted channel based on a comparison list provided by a set-top box provider, while analog TVs usually identify the current channel based on a frequency point list. Since the frequency point for a same channel varies across the country, it is very difficult to identify the channel shown by the analog TV set with the frequency point list.
The channel shown by the analog TV set may also be identified through TV station logo recognition. Since each channel has its own unique TV station logo, it is easy to know the channel name after recognizing the TV station logo of the current channel. A conventional method for recognizing TV station logo includes: obtaining a TV screen image, selecting a top quadrant area of the TV screen image as a matching area, then performing a graphic retrieval by substituting all the standard TV station logos pre-stored in a database into the matching area one by one, and finally selecting the standard TV station logo with a highest matching probability according to the matching probabilities obtained by the graphic retrieval as the TV station logo of the current TV channel. The graphic retrieval indicates matching the standard TV station logos in the database with the image in the matching area.
However, nowadays TV screens become larger as well as the selected matching area, which increases the resultant calculation required for the recognition. Thus, the TV station logo recognition according to the above method may be too slow.